[PATCH v8 0/2] GPCv2 power gating driver

[PATCH v8 0/2] GPCv2 power gating driver

[Andrey Smirnov]

Shawn,

Here's v8 of GPCv2 patches with more feedback from Dong incorporated.

Thanks,
Andrey Smirnov

Changes since v7 (see [v7]):

	- Drop the code to support USB OTG power domains and simplify
          a number of codepaths because of that

	- Add access table to regmap config to prevent accesses to
          undesired locations in the register file

	- Dropped cache type specifier from regmap config

	- Re-arrange constant definition to align more closesly with RM

	- Minor stylistic adjustments

Changes since v6 (see [v6]):

	- Drop .readable_reg related code

	- Switch regmap to REGCACHE_NONE and drop .volatile_reg

	- Remove unnecessary #include directives

Changes since v5 (see [v5]):

	- Apply reverse tree variable declartaion fromatting to
          imx_gpcv2_probe() and imx7_gpc_pu_pgc_sw_pxx_req()

	- Drop patch #3 in favour of defaulting to y in Kconfig
	
Changes since v4 (see [v4]):

	- Single patch is split into multiple as per Shawn's reques

	- Incorporated various feedback from Shawn

Changes since v3 (see [v3]):

	- Minor device tree bindings documentation fixes as per
          feedback from Rob Herring
	- Collect Acked-by from Rob

Changes since v2 (see [v2]):

	- Fix a critical bug where incorrect state of a bit was
          expected in a busy wait loop (bit set instead of bit
          cleared) imx7_gpc_pu_pgc_sw_pxx_req()

	- Add missing step (setting of PCR in GPC_PGC_nCTRL) in power
          down procedure

Changes since v1 (see [v1]):

	- Various small DT bindings description fixes as per feedback
          from Rob Herring


[v1] https://lkml.org/lkml/2017/2/6/554
[v2] https://lkml.org/lkml/2017/2/13/489
[v3] https://lkml.org/lkml/2017/2/20/338
[v4] https://lkml.org/lkml/2017/2/28/738
[v5] https://lkml.org/lkml/2017/3/14/547
[v6] https://lkml.org/lkml/2017/3/16/357
[v7] https://lkml.org/lkml/2017/3/21/405


Andrey Smirnov (2):
  dt-bindings: Add GPCv2 power gating driver
  soc/imx: Add GPCv2 power gating driver

 .../devicetree/bindings/power/fsl,imx-gpcv2.txt    |  71 ++++
 drivers/soc/Kconfig                                |   1 +
 drivers/soc/imx/Kconfig                            |  10 +
 drivers/soc/imx/Makefile                           |   1 +
 drivers/soc/imx/gpcv2.c                            | 363 +++++++++++++++++++++
 include/dt-bindings/power/imx7-power.h             |  16 +
 6 files changed, 462 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
 create mode 100644 drivers/soc/imx/Kconfig
 create mode 100644 drivers/soc/imx/gpcv2.c
 create mode 100644 include/dt-bindings/power/imx7-power.h

-- 
2.9.3

[PATCH v8 0/2] GPCv2 power gating driver

[Andrey Smirnov]

Shawn,

Here's v8 of GPCv2 patches with more feedback from Dong incorporated.

Thanks,
Andrey Smirnov

Changes since v7 (see [v7]):

	- Drop the code to support USB OTG power domains and simplify
          a number of codepaths because of that

	- Add access table to regmap config to prevent accesses to
          undesired locations in the register file

	- Dropped cache type specifier from regmap config

	- Re-arrange constant definition to align more closesly with RM

	- Minor stylistic adjustments

Changes since v6 (see [v6]):

	- Drop .readable_reg related code

	- Switch regmap to REGCACHE_NONE and drop .volatile_reg

	- Remove unnecessary #include directives

Changes since v5 (see [v5]):

	- Apply reverse tree variable declartaion fromatting to
          imx_gpcv2_probe() and imx7_gpc_pu_pgc_sw_pxx_req()

	- Drop patch #3 in favour of defaulting to y in Kconfig
	
Changes since v4 (see [v4]):

	- Single patch is split into multiple as per Shawn's reques

	- Incorporated various feedback from Shawn

Changes since v3 (see [v3]):

	- Minor device tree bindings documentation fixes as per
          feedback from Rob Herring
	- Collect Acked-by from Rob

Changes since v2 (see [v2]):

	- Fix a critical bug where incorrect state of a bit was
          expected in a busy wait loop (bit set instead of bit
          cleared) imx7_gpc_pu_pgc_sw_pxx_req()

	- Add missing step (setting of PCR in GPC_PGC_nCTRL) in power
          down procedure

Changes since v1 (see [v1]):

	- Various small DT bindings description fixes as per feedback
          from Rob Herring


[v1] https://lkml.org/lkml/2017/2/6/554
[v2] https://lkml.org/lkml/2017/2/13/489
[v3] https://lkml.org/lkml/2017/2/20/338
[v4] https://lkml.org/lkml/2017/2/28/738
[v5] https://lkml.org/lkml/2017/3/14/547
[v6] https://lkml.org/lkml/2017/3/16/357
[v7] https://lkml.org/lkml/2017/3/21/405


Andrey Smirnov (2):
  dt-bindings: Add GPCv2 power gating driver
  soc/imx: Add GPCv2 power gating driver

 .../devicetree/bindings/power/fsl,imx-gpcv2.txt    |  71 ++++
 drivers/soc/Kconfig                                |   1 +
 drivers/soc/imx/Kconfig                            |  10 +
 drivers/soc/imx/Makefile                           |   1 +
 drivers/soc/imx/gpcv2.c                            | 363 +++++++++++++++++++++
 include/dt-bindings/power/imx7-power.h             |  16 +
 6 files changed, 462 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
 create mode 100644 drivers/soc/imx/Kconfig
 create mode 100644 drivers/soc/imx/gpcv2.c
 create mode 100644 include/dt-bindings/power/imx7-power.h

-- 
2.9.3

[PATCH v8 1/2] dt-bindings: Add GPCv2 power gating driver

[Andrey Smirnov]

Add DT bindings for power domain driver for GPCv2 IP block found in
i.MX7 SoCs.

Cc: yurovsky@gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 .../devicetree/bindings/power/fsl,imx-gpcv2.txt    | 71 ++++++++++++++++++++++
 include/dt-bindings/power/imx7-power.h             | 16 +++++
 2 files changed, 87 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
 create mode 100644 include/dt-bindings/power/imx7-power.h

diff --git a/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
new file mode 100644
index 0000000..02f45c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
@@ -0,0 +1,71 @@
+Freescale i.MX General Power Controller v2
+==========================================
+
+The i.MX7S/D General Power Control (GPC) block contains Power Gating
+Control (PGC) for various power domains.
+
+Required properties:
+
+- compatible: Should be "fsl,imx7d-gpc"
+
+- reg: should be register base and length as documented in the
+  datasheet
+
+- interrupts: Should contain GPC interrupt request 1
+
+Power domains contained within GPC node are generic power domain
+providers, documented in
+Documentation/devicetree/bindings/power/power_domain.txt, which are
+described as subnodes of the power gating controller 'pgc' node,
+which, in turn, is expected to contain the following:
+
+Required properties:
+
+- reg: Power domain index. Valid values are defined in
+  include/dt-bindings/power/imx7-power.h
+
+- #power-domain-cells: Should be 0
+
+Optional properties:
+
+- power-supply: Power supply used to power the domain
+
+Example:
+
+	gpc: gpc@303a0000 {
+		compatible = "fsl,imx7d-gpc";
+		reg = <0x303a0000 0x1000>;
+		interrupt-controller;
+		interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
+		#interrupt-cells = <3>;
+		interrupt-parent = <&intc>;
+
+		pgc {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pgc_pcie_phy: power-domain@3 {
+				#power-domain-cells = <0>;
+
+				reg = <IMX7_POWER_DOMAIN_PCIE_PHY>;
+				power-supply = <&reg_1p0d>;
+			};
+		};
+	};
+
+
+Specifying power domain for IP modules
+======================================
+
+IP cores belonging to a power domain should contain a 'power-domains'
+property that is a phandle for PGC node representing the domain.
+
+Example of a device that is part of the PCIE_PHY power domain:
+
+	pcie: pcie@33800000 {
+	      reg = <0x33800000 0x4000>,
+	            <0x4ff00000 0x80000>;
+		/* ... */
+		power-domains = <&pgc_pcie_phy>;
+		/* ... */
+	};
diff --git a/include/dt-bindings/power/imx7-power.h b/include/dt-bindings/power/imx7-power.h
new file mode 100644
index 0000000..3a181e4
--- /dev/null
+++ b/include/dt-bindings/power/imx7-power.h
@@ -0,0 +1,16 @@
+/*
+ *  Copyright (C) 2017 Impinj
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __DT_BINDINGS_IMX7_POWER_H__
+#define __DT_BINDINGS_IMX7_POWER_H__
+
+#define IMX7_POWER_DOMAIN_MIPI_PHY		0
+#define IMX7_POWER_DOMAIN_PCIE_PHY		1
+#define IMX7_POWER_DOMAIN_USB_HSIC_PHY		2
+
+#endif
-- 
2.9.3

[PATCH v8 1/2] dt-bindings: Add GPCv2 power gating driver

[Andrey Smirnov]

Add DT bindings for power domain driver for GPCv2 IP block found in
i.MX7 SoCs.

Cc: yurovsky at gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: devicetree at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 .../devicetree/bindings/power/fsl,imx-gpcv2.txt    | 71 ++++++++++++++++++++++
 include/dt-bindings/power/imx7-power.h             | 16 +++++
 2 files changed, 87 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
 create mode 100644 include/dt-bindings/power/imx7-power.h

diff --git a/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
new file mode 100644
index 0000000..02f45c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/fsl,imx-gpcv2.txt
@@ -0,0 +1,71 @@
+Freescale i.MX General Power Controller v2
+==========================================
+
+The i.MX7S/D General Power Control (GPC) block contains Power Gating
+Control (PGC) for various power domains.
+
+Required properties:
+
+- compatible: Should be "fsl,imx7d-gpc"
+
+- reg: should be register base and length as documented in the
+  datasheet
+
+- interrupts: Should contain GPC interrupt request 1
+
+Power domains contained within GPC node are generic power domain
+providers, documented in
+Documentation/devicetree/bindings/power/power_domain.txt, which are
+described as subnodes of the power gating controller 'pgc' node,
+which, in turn, is expected to contain the following:
+
+Required properties:
+
+- reg: Power domain index. Valid values are defined in
+  include/dt-bindings/power/imx7-power.h
+
+- #power-domain-cells: Should be 0
+
+Optional properties:
+
+- power-supply: Power supply used to power the domain
+
+Example:
+
+	gpc: gpc at 303a0000 {
+		compatible = "fsl,imx7d-gpc";
+		reg = <0x303a0000 0x1000>;
+		interrupt-controller;
+		interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
+		#interrupt-cells = <3>;
+		interrupt-parent = <&intc>;
+
+		pgc {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pgc_pcie_phy: power-domain at 3 {
+				#power-domain-cells = <0>;
+
+				reg = <IMX7_POWER_DOMAIN_PCIE_PHY>;
+				power-supply = <&reg_1p0d>;
+			};
+		};
+	};
+
+
+Specifying power domain for IP modules
+======================================
+
+IP cores belonging to a power domain should contain a 'power-domains'
+property that is a phandle for PGC node representing the domain.
+
+Example of a device that is part of the PCIE_PHY power domain:
+
+	pcie: pcie at 33800000 {
+	      reg = <0x33800000 0x4000>,
+	            <0x4ff00000 0x80000>;
+		/* ... */
+		power-domains = <&pgc_pcie_phy>;
+		/* ... */
+	};
diff --git a/include/dt-bindings/power/imx7-power.h b/include/dt-bindings/power/imx7-power.h
new file mode 100644
index 0000000..3a181e4
--- /dev/null
+++ b/include/dt-bindings/power/imx7-power.h
@@ -0,0 +1,16 @@
+/*
+ *  Copyright (C) 2017 Impinj
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __DT_BINDINGS_IMX7_POWER_H__
+#define __DT_BINDINGS_IMX7_POWER_H__
+
+#define IMX7_POWER_DOMAIN_MIPI_PHY		0
+#define IMX7_POWER_DOMAIN_PCIE_PHY		1
+#define IMX7_POWER_DOMAIN_USB_HSIC_PHY		2
+
+#endif
-- 
2.9.3

[PATCH v8 2/2] soc/imx: Add GPCv2 power gating driver

[Andrey Smirnov]

Add code allowing for control of various power domains managed by GPCv2
IP block found in i.MX7 series of SoCs. Power domains covered by this
patch are:

    - PCIE PHY
    - MIPI PHY
    - USB HSIC PHY
    - USB OTG1/2 PHY

Support for any other power domain controlled by GPC is not present, and
can be added at some later point.

Testing of this code was done against a PCIe driver.

Cc: yurovsky@gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/soc/Kconfig      |   1 +
 drivers/soc/imx/Kconfig  |  10 ++
 drivers/soc/imx/Makefile |   1 +
 drivers/soc/imx/gpcv2.c  | 363 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 375 insertions(+)
 create mode 100644 drivers/soc/imx/Kconfig
 create mode 100644 drivers/soc/imx/gpcv2.c

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index f09023f..8943543 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -2,6 +2,7 @@ menu "SOC (System On Chip) specific Drivers"
 
 source "drivers/soc/bcm/Kconfig"
 source "drivers/soc/fsl/Kconfig"
+source "drivers/soc/imx/Kconfig"
 source "drivers/soc/mediatek/Kconfig"
 source "drivers/soc/qcom/Kconfig"
 source "drivers/soc/rockchip/Kconfig"
diff --git a/drivers/soc/imx/Kconfig b/drivers/soc/imx/Kconfig
new file mode 100644
index 0000000..bc7f0ee0
--- /dev/null
+++ b/drivers/soc/imx/Kconfig
@@ -0,0 +1,10 @@
+menu "i.MX SoC drivers"
+
+config IMX7_PM_DOMAINS
+	bool "i.MX7 PM domains"
+	select PM_GENERIC_DOMAINS
+	depends on SOC_IMX7D || (COMPILE_TEST && OF)
+	default y if SOC_IMX7D
+
+endmenu
+
diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
index 35861f5..5b6e396 100644
--- a/drivers/soc/imx/Makefile
+++ b/drivers/soc/imx/Makefile
@@ -1 +1,2 @@
 obj-y += gpc.o
+obj-$(CONFIG_IMX7_PM_DOMAINS) += gpcv2.o
diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
new file mode 100644
index 0000000..3039072
--- /dev/null
+++ b/drivers/soc/imx/gpcv2.c
@@ -0,0 +1,363 @@
+/*
+ * Copyright 2017 Impinj, Inc
+ * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
+ *
+ * Based on the code of analogus driver:
+ *
+ * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <dt-bindings/power/imx7-power.h>
+
+#define GPC_LPCR_A7_BSC			0x000
+
+#define GPC_PGC_CPU_MAPPING		0x0ec
+#define USB_HSIC_PHY_A7_DOMAIN		BIT(6)
+#define USB_OTG2_PHY_A7_DOMAIN		BIT(5)
+#define USB_OTG1_PHY_A7_DOMAIN		BIT(4)
+#define PCIE_PHY_A7_DOMAIN		BIT(3)
+#define MIPI_PHY_A7_DOMAIN		BIT(2)
+
+#define GPC_PU_PGC_SW_PUP_REQ		0x0f8
+#define GPC_PU_PGC_SW_PDN_REQ		0x104
+#define USB_HSIC_PHY_SW_Pxx_REQ		BIT(4)
+#define USB_OTG2_PHY_SW_Pxx_REQ		BIT(3)
+#define USB_OTG1_PHY_SW_Pxx_REQ		BIT(2)
+#define PCIE_PHY_SW_Pxx_REQ		BIT(1)
+#define MIPI_PHY_SW_Pxx_REQ		BIT(0)
+
+#define GPC_M4_PU_PDN_FLG		0x1bc
+
+
+#define PGC_MIPI			4
+#define PGC_PCIE			5
+#define PGC_USB_HSIC			8
+#define GPC_PGC_CTRL(n)			(0x800 + (n) * 0x40)
+#define GPC_PGC_SR(n)			(GPC_PGC_CTRL(n) + 0xc)
+
+#define GPC_PGC_CTRL_PCR		BIT(0)
+
+struct imx7_pgc_domain {
+	struct generic_pm_domain genpd;
+	struct regmap *regmap;
+	struct regulator *regulator;
+
+	unsigned int pgc;
+
+	const struct {
+		u32 pxx;
+		u32 map;
+	} bits;
+
+	const int voltage;
+	struct device *dev;
+};
+
+static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
+				      bool on)
+{
+	struct imx7_pgc_domain *domain = container_of(genpd,
+						      struct imx7_pgc_domain,
+						      genpd);
+	unsigned int offset = on ?
+		GPC_PU_PGC_SW_PUP_REQ : GPC_PU_PGC_SW_PDN_REQ;
+	const bool enable_power_control = !on;
+	const bool has_regulator = !IS_ERR(domain->regulator);
+	unsigned long deadline;
+	int ret = 0;
+
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, domain->bits.map);
+
+	if (has_regulator && on) {
+		ret = regulator_enable(domain->regulator);
+		if (ret) {
+			dev_err(domain->dev, "failed to enable regulator\n");
+			goto unmap;
+		}
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+				   GPC_PGC_CTRL_PCR, GPC_PGC_CTRL_PCR);
+
+	regmap_update_bits(domain->regmap, offset,
+			   domain->bits.pxx, domain->bits.pxx);
+
+	/*
+	 * As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
+	 * for PUP_REQ/PDN_REQ bit to be cleared
+	 */
+	deadline = jiffies + msecs_to_jiffies(1);
+	while (true) {
+		u32 pxx_req;
+
+		regmap_read(domain->regmap, offset, &pxx_req);
+
+		if (!(pxx_req & domain->bits.pxx))
+			break;
+
+		if (time_after(jiffies, deadline)) {
+			dev_err(domain->dev, "falied to command PGC\n");
+			ret = -ETIMEDOUT;
+			/*
+			 * If we were in a process of enabling a
+			 * domain and failed we might as well disable
+			 * the regulator we just enabled. And if it
+			 * was the opposite situation and we failed to
+			 * power down -- keep the regulator on
+			 */
+			on = !on;
+			break;
+		}
+
+		cpu_relax();
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+				   GPC_PGC_CTRL_PCR, 0);
+
+	if (has_regulator && !on) {
+		int err;
+
+		err = regulator_disable(domain->regulator);
+		if (err)
+			dev_err(domain->dev,
+				"failed to disable regulator: %d\n", ret);
+		/* Preserve earlier error code */
+		ret = ret ?: err;
+	}
+unmap:
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, 0);
+	return ret;
+}
+
+static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
+}
+
+static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
+}
+
+static struct imx7_pgc_domain imx7_pgc_domains[] = {
+	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
+		.genpd = {
+			.name      = "mipi-phy",
+		},
+		.bits  = {
+			.pxx = MIPI_PHY_SW_Pxx_REQ,
+			.map = MIPI_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc	   = PGC_MIPI,
+	},
+
+	[IMX7_POWER_DOMAIN_PCIE_PHY] = {
+		.genpd = {
+			.name      = "pcie-phy",
+		},
+		.bits  = {
+			.pxx = PCIE_PHY_SW_Pxx_REQ,
+			.map = PCIE_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc	   = PGC_PCIE,
+	},
+
+	[IMX7_POWER_DOMAIN_USB_HSIC_PHY] = {
+		.genpd = {
+			.name      = "usb-hsic-phy",
+		},
+		.bits  = {
+			.pxx = USB_HSIC_PHY_SW_Pxx_REQ,
+			.map = USB_HSIC_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1200000,
+		.pgc	   = PGC_USB_HSIC,
+	},
+};
+
+static int imx7_pgc_domain_probe(struct platform_device *pdev)
+{
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+	int ret;
+
+	domain->dev = &pdev->dev;
+
+	ret = pm_genpd_init(&domain->genpd, NULL, true);
+	if (ret) {
+		dev_err(domain->dev, "Failed to init power domain\n");
+		return ret;
+	}
+
+	domain->regulator = devm_regulator_get_optional(domain->dev, "power");
+	if (IS_ERR(domain->regulator)) {
+		if (PTR_ERR(domain->regulator) != -ENODEV) {
+			dev_err(domain->dev, "Failed to get domain's regulator\n");
+			return PTR_ERR(domain->regulator);
+		}
+	} else {
+		regulator_set_voltage(domain->regulator,
+				      domain->voltage, domain->voltage);
+	}
+
+	ret = of_genpd_add_provider_simple(domain->dev->of_node,
+					   &domain->genpd);
+	if (ret) {
+		dev_err(domain->dev, "Failed to add genpd provider\n");
+		pm_genpd_remove(&domain->genpd);
+	}
+
+	return ret;
+}
+
+static int imx7_pgc_domain_remove(struct platform_device *pdev)
+{
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+
+	of_genpd_del_provider(domain->dev->of_node);
+	pm_genpd_remove(&domain->genpd);
+
+	return 0;
+}
+
+static const struct platform_device_id imx7_pgc_domain_id[] = {
+	{ "imx7-pgc-domain", },
+	{ },
+};
+
+static struct platform_driver imx7_pgc_domain_driver = {
+	.driver = {
+		.name = "imx7-pgc",
+	},
+	.probe    = imx7_pgc_domain_probe,
+	.remove   = imx7_pgc_domain_remove,
+	.id_table = imx7_pgc_domain_id,
+};
+builtin_platform_driver(imx7_pgc_domain_driver)
+
+static int imx_gpcv2_probe(struct platform_device *pdev)
+{
+	static const struct regmap_range yes_ranges[] = {
+		regmap_reg_range(GPC_LPCR_A7_BSC,
+				 GPC_M4_PU_PDN_FLG),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_MIPI),
+				 GPC_PGC_SR(PGC_MIPI)),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_PCIE),
+				 GPC_PGC_SR(PGC_PCIE)),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_USB_HSIC),
+				 GPC_PGC_SR(PGC_USB_HSIC)),
+	};
+	static const struct regmap_access_table access_table = {
+		.yes_ranges	= yes_ranges,
+		.n_yes_ranges	= ARRAY_SIZE(yes_ranges),
+	};
+	static const struct regmap_config regmap_config = {
+		.reg_bits	= 32,
+		.val_bits	= 32,
+		.reg_stride	= 4,
+		.rd_table	= &access_table,
+		.wr_table	= &access_table,
+		.max_register   = SZ_4K,
+	};
+	struct device *dev = &pdev->dev;
+	struct device_node *pgc_np, *np;
+	struct regmap *regmap;
+	struct resource *res;
+	void __iomem *base;
+	int ret;
+
+	pgc_np = of_get_child_by_name(dev->of_node, "pgc");
+	if (!pgc_np) {
+		dev_err(dev, "No power domains specified in DT\n");
+		return -EINVAL;
+	}
+
+	res  = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(dev, "failed to init regmap (%d)\n", ret);
+		return ret;
+	}
+
+	for_each_child_of_node(pgc_np, np) {
+		struct platform_device *pd_pdev;
+		struct imx7_pgc_domain *domain;
+		u32 domain_index;
+
+		ret = of_property_read_u32(np, "reg", &domain_index);
+		if (ret) {
+			dev_err(dev, "Failed to read 'reg' property\n");
+			of_node_put(np);
+			return ret;
+		}
+
+		if (domain_index >= ARRAY_SIZE(imx7_pgc_domains)) {
+			dev_warn(dev,
+				 "Domain index %d is out of bounds\n",
+				 domain_index);
+			continue;
+		}
+
+		domain = &imx7_pgc_domains[domain_index];
+		domain->regmap = regmap;
+		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
+		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
+
+		pd_pdev = platform_device_alloc("imx7-pgc-domain",
+						domain_index);
+		if (!pd_pdev) {
+			dev_err(dev, "Failed to allocate platform device\n");
+			of_node_put(np);
+			return -ENOMEM;
+		}
+
+		pd_pdev->dev.platform_data = domain;
+		pd_pdev->dev.parent = dev;
+		pd_pdev->dev.of_node = np;
+
+		ret = platform_device_add(pd_pdev);
+		if (ret) {
+			platform_device_put(pd_pdev);
+			of_node_put(np);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct of_device_id imx_gpcv2_dt_ids[] = {
+	{ .compatible = "fsl,imx7d-gpc" },
+	{ }
+};
+
+static struct platform_driver imx_gpc_driver = {
+	.driver = {
+		.name = "imx-gpcv2",
+		.of_match_table = imx_gpcv2_dt_ids,
+	},
+	.probe = imx_gpcv2_probe,
+};
+builtin_platform_driver(imx_gpc_driver)
-- 
2.9.3

[PATCH v8 2/2] soc/imx: Add GPCv2 power gating driver

[Andrey Smirnov]

Add code allowing for control of various power domains managed by GPCv2
IP block found in i.MX7 series of SoCs. Power domains covered by this
patch are:

    - PCIE PHY
    - MIPI PHY
    - USB HSIC PHY
    - USB OTG1/2 PHY

Support for any other power domain controlled by GPC is not present, and
can be added at some later point.

Testing of this code was done against a PCIe driver.

Cc: yurovsky at gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/soc/Kconfig      |   1 +
 drivers/soc/imx/Kconfig  |  10 ++
 drivers/soc/imx/Makefile |   1 +
 drivers/soc/imx/gpcv2.c  | 363 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 375 insertions(+)
 create mode 100644 drivers/soc/imx/Kconfig
 create mode 100644 drivers/soc/imx/gpcv2.c

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index f09023f..8943543 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -2,6 +2,7 @@ menu "SOC (System On Chip) specific Drivers"
 
 source "drivers/soc/bcm/Kconfig"
 source "drivers/soc/fsl/Kconfig"
+source "drivers/soc/imx/Kconfig"
 source "drivers/soc/mediatek/Kconfig"
 source "drivers/soc/qcom/Kconfig"
 source "drivers/soc/rockchip/Kconfig"
diff --git a/drivers/soc/imx/Kconfig b/drivers/soc/imx/Kconfig
new file mode 100644
index 0000000..bc7f0ee0
--- /dev/null
+++ b/drivers/soc/imx/Kconfig
@@ -0,0 +1,10 @@
+menu "i.MX SoC drivers"
+
+config IMX7_PM_DOMAINS
+	bool "i.MX7 PM domains"
+	select PM_GENERIC_DOMAINS
+	depends on SOC_IMX7D || (COMPILE_TEST && OF)
+	default y if SOC_IMX7D
+
+endmenu
+
diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
index 35861f5..5b6e396 100644
--- a/drivers/soc/imx/Makefile
+++ b/drivers/soc/imx/Makefile
@@ -1 +1,2 @@
 obj-y += gpc.o
+obj-$(CONFIG_IMX7_PM_DOMAINS) += gpcv2.o
diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
new file mode 100644
index 0000000..3039072
--- /dev/null
+++ b/drivers/soc/imx/gpcv2.c
@@ -0,0 +1,363 @@
+/*
+ * Copyright 2017 Impinj, Inc
+ * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
+ *
+ * Based on the code of analogus driver:
+ *
+ * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <dt-bindings/power/imx7-power.h>
+
+#define GPC_LPCR_A7_BSC			0x000
+
+#define GPC_PGC_CPU_MAPPING		0x0ec
+#define USB_HSIC_PHY_A7_DOMAIN		BIT(6)
+#define USB_OTG2_PHY_A7_DOMAIN		BIT(5)
+#define USB_OTG1_PHY_A7_DOMAIN		BIT(4)
+#define PCIE_PHY_A7_DOMAIN		BIT(3)
+#define MIPI_PHY_A7_DOMAIN		BIT(2)
+
+#define GPC_PU_PGC_SW_PUP_REQ		0x0f8
+#define GPC_PU_PGC_SW_PDN_REQ		0x104
+#define USB_HSIC_PHY_SW_Pxx_REQ		BIT(4)
+#define USB_OTG2_PHY_SW_Pxx_REQ		BIT(3)
+#define USB_OTG1_PHY_SW_Pxx_REQ		BIT(2)
+#define PCIE_PHY_SW_Pxx_REQ		BIT(1)
+#define MIPI_PHY_SW_Pxx_REQ		BIT(0)
+
+#define GPC_M4_PU_PDN_FLG		0x1bc
+
+
+#define PGC_MIPI			4
+#define PGC_PCIE			5
+#define PGC_USB_HSIC			8
+#define GPC_PGC_CTRL(n)			(0x800 + (n) * 0x40)
+#define GPC_PGC_SR(n)			(GPC_PGC_CTRL(n) + 0xc)
+
+#define GPC_PGC_CTRL_PCR		BIT(0)
+
+struct imx7_pgc_domain {
+	struct generic_pm_domain genpd;
+	struct regmap *regmap;
+	struct regulator *regulator;
+
+	unsigned int pgc;
+
+	const struct {
+		u32 pxx;
+		u32 map;
+	} bits;
+
+	const int voltage;
+	struct device *dev;
+};
+
+static int imx7_gpc_pu_pgc_sw_pxx_req(struct generic_pm_domain *genpd,
+				      bool on)
+{
+	struct imx7_pgc_domain *domain = container_of(genpd,
+						      struct imx7_pgc_domain,
+						      genpd);
+	unsigned int offset = on ?
+		GPC_PU_PGC_SW_PUP_REQ : GPC_PU_PGC_SW_PDN_REQ;
+	const bool enable_power_control = !on;
+	const bool has_regulator = !IS_ERR(domain->regulator);
+	unsigned long deadline;
+	int ret = 0;
+
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, domain->bits.map);
+
+	if (has_regulator && on) {
+		ret = regulator_enable(domain->regulator);
+		if (ret) {
+			dev_err(domain->dev, "failed to enable regulator\n");
+			goto unmap;
+		}
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+				   GPC_PGC_CTRL_PCR, GPC_PGC_CTRL_PCR);
+
+	regmap_update_bits(domain->regmap, offset,
+			   domain->bits.pxx, domain->bits.pxx);
+
+	/*
+	 * As per "5.5.9.4 Example Code 4" in IMX7DRM.pdf wait
+	 * for PUP_REQ/PDN_REQ bit to be cleared
+	 */
+	deadline = jiffies + msecs_to_jiffies(1);
+	while (true) {
+		u32 pxx_req;
+
+		regmap_read(domain->regmap, offset, &pxx_req);
+
+		if (!(pxx_req & domain->bits.pxx))
+			break;
+
+		if (time_after(jiffies, deadline)) {
+			dev_err(domain->dev, "falied to command PGC\n");
+			ret = -ETIMEDOUT;
+			/*
+			 * If we were in a process of enabling a
+			 * domain and failed we might as well disable
+			 * the regulator we just enabled. And if it
+			 * was the opposite situation and we failed to
+			 * power down -- keep the regulator on
+			 */
+			on = !on;
+			break;
+		}
+
+		cpu_relax();
+	}
+
+	if (enable_power_control)
+		regmap_update_bits(domain->regmap, GPC_PGC_CTRL(domain->pgc),
+				   GPC_PGC_CTRL_PCR, 0);
+
+	if (has_regulator && !on) {
+		int err;
+
+		err = regulator_disable(domain->regulator);
+		if (err)
+			dev_err(domain->dev,
+				"failed to disable regulator: %d\n", ret);
+		/* Preserve earlier error code */
+		ret = ret ?: err;
+	}
+unmap:
+	regmap_update_bits(domain->regmap, GPC_PGC_CPU_MAPPING,
+			   domain->bits.map, 0);
+	return ret;
+}
+
+static int imx7_gpc_pu_pgc_sw_pup_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, true);
+}
+
+static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
+{
+	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
+}
+
+static struct imx7_pgc_domain imx7_pgc_domains[] = {
+	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
+		.genpd = {
+			.name      = "mipi-phy",
+		},
+		.bits  = {
+			.pxx = MIPI_PHY_SW_Pxx_REQ,
+			.map = MIPI_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc	   = PGC_MIPI,
+	},
+
+	[IMX7_POWER_DOMAIN_PCIE_PHY] = {
+		.genpd = {
+			.name      = "pcie-phy",
+		},
+		.bits  = {
+			.pxx = PCIE_PHY_SW_Pxx_REQ,
+			.map = PCIE_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1000000,
+		.pgc	   = PGC_PCIE,
+	},
+
+	[IMX7_POWER_DOMAIN_USB_HSIC_PHY] = {
+		.genpd = {
+			.name      = "usb-hsic-phy",
+		},
+		.bits  = {
+			.pxx = USB_HSIC_PHY_SW_Pxx_REQ,
+			.map = USB_HSIC_PHY_A7_DOMAIN,
+		},
+		.voltage   = 1200000,
+		.pgc	   = PGC_USB_HSIC,
+	},
+};
+
+static int imx7_pgc_domain_probe(struct platform_device *pdev)
+{
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+	int ret;
+
+	domain->dev = &pdev->dev;
+
+	ret = pm_genpd_init(&domain->genpd, NULL, true);
+	if (ret) {
+		dev_err(domain->dev, "Failed to init power domain\n");
+		return ret;
+	}
+
+	domain->regulator = devm_regulator_get_optional(domain->dev, "power");
+	if (IS_ERR(domain->regulator)) {
+		if (PTR_ERR(domain->regulator) != -ENODEV) {
+			dev_err(domain->dev, "Failed to get domain's regulator\n");
+			return PTR_ERR(domain->regulator);
+		}
+	} else {
+		regulator_set_voltage(domain->regulator,
+				      domain->voltage, domain->voltage);
+	}
+
+	ret = of_genpd_add_provider_simple(domain->dev->of_node,
+					   &domain->genpd);
+	if (ret) {
+		dev_err(domain->dev, "Failed to add genpd provider\n");
+		pm_genpd_remove(&domain->genpd);
+	}
+
+	return ret;
+}
+
+static int imx7_pgc_domain_remove(struct platform_device *pdev)
+{
+	struct imx7_pgc_domain *domain = pdev->dev.platform_data;
+
+	of_genpd_del_provider(domain->dev->of_node);
+	pm_genpd_remove(&domain->genpd);
+
+	return 0;
+}
+
+static const struct platform_device_id imx7_pgc_domain_id[] = {
+	{ "imx7-pgc-domain", },
+	{ },
+};
+
+static struct platform_driver imx7_pgc_domain_driver = {
+	.driver = {
+		.name = "imx7-pgc",
+	},
+	.probe    = imx7_pgc_domain_probe,
+	.remove   = imx7_pgc_domain_remove,
+	.id_table = imx7_pgc_domain_id,
+};
+builtin_platform_driver(imx7_pgc_domain_driver)
+
+static int imx_gpcv2_probe(struct platform_device *pdev)
+{
+	static const struct regmap_range yes_ranges[] = {
+		regmap_reg_range(GPC_LPCR_A7_BSC,
+				 GPC_M4_PU_PDN_FLG),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_MIPI),
+				 GPC_PGC_SR(PGC_MIPI)),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_PCIE),
+				 GPC_PGC_SR(PGC_PCIE)),
+		regmap_reg_range(GPC_PGC_CTRL(PGC_USB_HSIC),
+				 GPC_PGC_SR(PGC_USB_HSIC)),
+	};
+	static const struct regmap_access_table access_table = {
+		.yes_ranges	= yes_ranges,
+		.n_yes_ranges	= ARRAY_SIZE(yes_ranges),
+	};
+	static const struct regmap_config regmap_config = {
+		.reg_bits	= 32,
+		.val_bits	= 32,
+		.reg_stride	= 4,
+		.rd_table	= &access_table,
+		.wr_table	= &access_table,
+		.max_register   = SZ_4K,
+	};
+	struct device *dev = &pdev->dev;
+	struct device_node *pgc_np, *np;
+	struct regmap *regmap;
+	struct resource *res;
+	void __iomem *base;
+	int ret;
+
+	pgc_np = of_get_child_by_name(dev->of_node, "pgc");
+	if (!pgc_np) {
+		dev_err(dev, "No power domains specified in DT\n");
+		return -EINVAL;
+	}
+
+	res  = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
+	if (IS_ERR(regmap)) {
+		ret = PTR_ERR(regmap);
+		dev_err(dev, "failed to init regmap (%d)\n", ret);
+		return ret;
+	}
+
+	for_each_child_of_node(pgc_np, np) {
+		struct platform_device *pd_pdev;
+		struct imx7_pgc_domain *domain;
+		u32 domain_index;
+
+		ret = of_property_read_u32(np, "reg", &domain_index);
+		if (ret) {
+			dev_err(dev, "Failed to read 'reg' property\n");
+			of_node_put(np);
+			return ret;
+		}
+
+		if (domain_index >= ARRAY_SIZE(imx7_pgc_domains)) {
+			dev_warn(dev,
+				 "Domain index %d is out of bounds\n",
+				 domain_index);
+			continue;
+		}
+
+		domain = &imx7_pgc_domains[domain_index];
+		domain->regmap = regmap;
+		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
+		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
+
+		pd_pdev = platform_device_alloc("imx7-pgc-domain",
+						domain_index);
+		if (!pd_pdev) {
+			dev_err(dev, "Failed to allocate platform device\n");
+			of_node_put(np);
+			return -ENOMEM;
+		}
+
+		pd_pdev->dev.platform_data = domain;
+		pd_pdev->dev.parent = dev;
+		pd_pdev->dev.of_node = np;
+
+		ret = platform_device_add(pd_pdev);
+		if (ret) {
+			platform_device_put(pd_pdev);
+			of_node_put(np);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct of_device_id imx_gpcv2_dt_ids[] = {
+	{ .compatible = "fsl,imx7d-gpc" },
+	{ }
+};
+
+static struct platform_driver imx_gpc_driver = {
+	.driver = {
+		.name = "imx-gpcv2",
+		.of_match_table = imx_gpcv2_dt_ids,
+	},
+	.probe = imx_gpcv2_probe,
+};
+builtin_platform_driver(imx_gpc_driver)
-- 
2.9.3

Re: [PATCH v8 0/2] GPCv2 power gating driver

[Shawn Guo]

On Tue, Mar 28, 2017 at 08:19:43AM -0700, Andrey Smirnov wrote:
> Andrey Smirnov (2):
>   dt-bindings: Add GPCv2 power gating driver
>   soc/imx: Add GPCv2 power gating driver

Changed prefix like 'soc: imx: ...', and applied both.

Shawn

[PATCH v8 0/2] GPCv2 power gating driver

[Shawn Guo]

On Tue, Mar 28, 2017 at 08:19:43AM -0700, Andrey Smirnov wrote:
> Andrey Smirnov (2):
>   dt-bindings: Add GPCv2 power gating driver
>   soc/imx: Add GPCv2 power gating driver

Changed prefix like 'soc: imx: ...', and applied both.

Shawn